一、单项选择题(共20小题；每小题1分，满分20分)
1. Great changes ______ in China in the past 20 years.
A. took place B. have taken place
C. were taken place D. have been taken place
2. The manager meant ____ the workers that being 5 minutes late meant ____ the company.
A. to tell, to leave B. telling, leaving
C. to tell, leaving D. telling, to leave
